This invention relates to a bi-directional heat exchange structure that acts as both a high efficiency self-regulating evaporator and a high-contact angle condensation surface.
Thermo-adsorptive batteries store and release heat. Such thermal batteries may include hydrophilic nanostructured porous media, often copper, to enhance evaporation and condensation. Sintered copper particles, compressed open-cell copper foams and diffusion bonded metal mesh have been used as porous media for evaporation in the prior art. However, a limitation of these metallic substrates is the adsorption of organic contaminants in the course of normal operation which renders them either neutrally wetting or hydrophobic and therefore completely nonfunctional after a period of hours or days in normal operation.
An object of the present invention, therefore, is a heat exchange porous structure in which nanostructures therein are formed substantially uniformly throughout the porous structure to make the porous structure permanently hydrophilic in the presence of organic contaminants.